Spark-plug



P. V. CARPENTER.

SPARK PLUG. APPLICATION FILED JUNE 17, l9l9- 1,401,670, Patented Dec. 27, 1921.

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Specificationof Letterslatent. Patented Dec. 2%, i921,

Continuation in part of application Serial No. 254,410, filed September 17, 1918. This application filed,

June 17, 1919. Serial No. 304,769.

To all whom, it may concern:

Be it known that I, Punva V. CARPENTER, a. citizen of the United States, residin at Worth, in the county of Gaston and tate of North Carolina, have invented certain improvements in spark plugs particularly aiming to improve that type in which a priming cock is mounted upon the side of the plug with the passage leading-therefrom to the interior, and seeks to so coordinate the priming device, its passage, and the electrodes of the plug that a cleaning tool may be introduced through the priming passage to clean the electrodes. It is a specific aim of the invention to improve the construction of electrode, particularly the one mounted upon the plug case, whereby the strength of the electrode will be increased and its ignition eiiiciency also improved. It is a further aim to improve the manner of mounting the electrode upon the casd.

Additional objects and advantages and features of invention will appear from the construction, arrangement and combination of parts hereinafter described and shown in the drawings, wherein,

Figure 1 is a vertical longitudinal sectional view of a plug constructed in accordance with my invention,

Fig. 2 is a bottom view thereof,

- Fig. 3 is a vertical sectional view at right angles to Fig. 1,

Fig. 4 is a fragmentary elevation of the lower end of the plug, considerably enlarged, showin the manner of mounting the case electro e.

Fig. 5 is an edge View of a file adapted to be? inserted through the passage 22 of the plug for cleaning thereof.

There is illustrated a spark plug case 10, which corresponds to the usual shell of spark plugs now generally known, havin a lower threaded cylindrical portion 11 a apted to be screwed into the cylinder tapping, and a substantially hexagonal upper part forming a nut portion 12, the faces 13 of which are adapted to receive a wrench for the emplacement or removal of the plug upon a motor. The plugis provided with a lateral enlar ement, however, at one side, occupying t e full width of one of the faces 13, and taking the place of one such face, being flattened at its outer side as at 15 to form a face parallel to the face 13, at the opposite side of the plug, so that a wrench may still be engaged with one jaw against the enlargement, and one jaw against the opposite. face 13. In the casing there is mounted in a familiar way a porcelain 17 carryin an insulated electrode 18, which isprefera ly of of an inch in diameter, its end being tapered as illustrated and stopping close to the plane in which the lower end of the shell terminates. A casing electrode 19 is mounted upon the end of the casing, this electrode comprising a strip of resilient sheet metal having a base or outer part 20 set in a kerf extending transversely across the end edge of the shell at one side, being snugly fitted therein, and the material of the shell at each side peened so as to be upset over the electrode 19, the sides of which are slightly inclined inwardly as shown in Fig. 4, forming a dove-tailed fit, or, the electrode may be given'a slightly dove-tailed form before introduction in the kerf, in order to facilitate this character of joint. The inner part of the electrode is twisted slightly less than one-quarter turn, so that while one edge lies outwardly of the end of the electrode 18, the other is extended inwardly a distance within the end of the plug casing as shown.

Formed in the enlargement 14 there is an inclined passage way 22, the axis of which coincides with a line drawn between the electrodes 18 and 19, the porcelain 17 being of a length at its inner orlow'er part to stop short of the inner end of the passage. as shown. The enlargement 1 1- is formed with a fiat outer face or top face'24, in which. there is formed a circular recess25, so located that its outer edge falls in line with or outwardly of the outer side of the passage 22, the recess communicating with the opposed surfaces of the electrodes 18 and 19 by being forced therebetween. The upper end of the passage 22 immediately adjacent the recess 25 is closed by means of a plug 26, held in place by means of a small spring 27 confined within a'washer and cotter pin at 28 upon a reduced stem 29 of the valve, the spring bearing against the side of the plug casingas will be understood. The passage through the valve may be made equal in size to the passage 22, in order to permit the introduction of a cleaning tool, or the valve may be removed to enable the ready introduction of a. tool, as found preferable. Such a tool is available, in the form of a file, as illustrated in Fig. 5.

lhis application is a continuation of my prior application, Serial Number 254,410, with respect to the claims allowed in that application and numbered 1, 2, and 3, herein.

What-is claimed-z 1. A plug of the character described comprising a casing body having a terminal end threaded for engagement in a cylinder head or the like, a diagonal valved passage and a concentric passage therein, a porcelain slidably engageable in and secured in the last named' passage, electrodes at the inner part of the plug, one being mounted in the porcelain 0n the axis of the plug, and located with their opposed surfaces equally spaced from and closely adjacent the medial line of said passage, said porcelain stopping short of the end of the diagonal passage, one

of said electrodes being resilient and laterally movable, whereby a file device inserted through said passage may be reciprocated between the points to clean them as described.

2. A. plug of the character described including a casing body having a diagonal valved passage therein, a porcelain removably mounted in the casing, and stopping short of the line of said diagonal passage, an electrode therein terminating in line with said passage, and an electrode on the inner part of the casing immediately adjacent the passage, the opposed surfaces of said electrodes being closely adjacent the medial line of said passage.

In testimony whereof I have aliixed my I signature in presence of two witnesses:

PUB-VA. V. CARPENTER.

"Witnesses:

A. J. lKEAnNs, H. C. WALKER. 

